Project Summary- Core B The overall theme of this program is to determine the mechanisms underlying sympathetic nerve activation caused by chronic intermittent hypoxia (CIH), a major manifestation of sleep apnea. All projects require exposing either intact, un-sedated rodents or cell cultures to an IH paradigm mimicking the blood O2 saturation profiles encountered during sleep apnea. Use of the same IH paradigm across all projects is essential as it allows longitudinal integration of results. This goal will be best accomplished by a centralized scientific facility. All projects utilize genetically engineered mice. Scientific Core provides centralized facilities with dedicated scientific personnel overseeing the genotyping and maintaining breeding colonies, which otherwise is cost prohibitive for individual projects. All projects in this program propose a variety of biochemical and molecular biology assays as well as morphology studies that are common amongst projects. Performing these assays under the Scientific Core is economical and allows use of the common reagents; antibodies etc. and more importantly provide quality control. Thus, the overall goal of the Scientific Core is to support centralized scientific services to all four projects proposed. The following are the SPECIFIC AIMS of the Scientific Core. AIM 1: Provide centralized facility for exposure of animals and cell cultures to intermittent hypoxia. AIM 2: Provides biochemical and molecular biological assays. AIM 3: Provide morphology assays. AIM 4: Provide help with statistical analysis of the data. The Scientific Core will be directed by Dr. Y-J- Peng, an experienced cardio-respiratory physiologist. Key Personnel include: Drs. J. Nanduri (expertise- biochemical and molecular biology approaches, A.J. Garcia (expertise- generating mice with targeted disruption of genes) and D. Nicolae (expertise- statistical and computational modeling and analyses). Key personnel will be assisted by Staff Members including Dr. S.A. Khan, Ms. N. Wang and Mr. B. Wang. The Scientific Core is situated at the Institute for Integrative Physiology (IIP) of the University of Chicago, where most of the proposed research will be conducted.